Lattice deformation and phase transformation from nano-scale anatase to nano-scale rutile TiO2 prepared by a sol-gel technique--颗粒学报PARTICUOLOGY

Shao, Y., Tang, D., Sun, J., Lee, Y., & Xiong, W. (2004). Lattice deformation and phase transformation from nano-scale anatase to nano-scale rutile TiO2 prepared by a sol-gel technique. China Particuology, 2(3), 119-123. https://doi.org/10.1016/S1672-2515(07)60036-0

Lattice deformation and phase transformation from nano-scale anatase to nano-scale rutile TiO₂ prepared by a sol-gel technique

Yanqun Shao ^{a b *}, Dian Tang ^{b c}, Jinghua Sun ^c, Yekun Lee ^c, Weihao Xiong ^a

a State Key Laboratory of Die & Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
b Institute for Materials Research, Fuzhou University, Fuzhou 350002, P. R. China
c Materials Research Center, University of Missouri-Rolla, Missouri, Rolla, MO65401, USA

10.1016/S1672-2515(07)60036-0

Volume 2, Issue 3, June 2004, Pages 119-123

Received 4 April 2004, Accepted 15 May 2004, Available online 27 November 2007.

E-mail: yqshao1989@163.com

Highlights

Abstract

Nano-scale rutile phase was transformed from nano-scale anatase upon heating, which was prepared by a sol-gel technique. The XRD data corresponding to the anatase and rutile phases were analyzed and the grain sizes of as-derived phases were calculated by Sherrer equation. The lattice parameters of the as-derived anatase and rutile unit cells were calculated and compared with those of standard lattice parameters on PDF cards. It was shown that the smaller the grain sizes, the larger the lattice deformation. The lattice parameter a has the negative deviation from the standard and the lattice parameter c has the positive deviation for both phases. The particles sizes had preferential influence on the longer parameter between the lattice parameters of a and c. With increasing temperatures, the lattice parameters of a and c in both phases approached to the equilibrium state. The larger lattice deformation facilitated the nucleation process, which lowered the transformation temperature. During the transformation from nano-scale anatase to rutile, besides the mechanism involving retention of the {112} pseudo-close-packed planes of oxygen in anatase as the {100} pseudo-close-packed planes in rutile, the new phase occurred by relaxation of lattice deformation and adjustment of the atomic sites in parent phase. The orientation relationships were suggested to be anatase {101}//rutile {101} and anatase <201>//rutile<111>, and the habit plane was anatase (101).

Graphical abstract

Keywords

nano-scale materials; anatase; rutile; phase transformation; TiO₂; sol-gel technique

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